After the free-school movement first began, the Kings Science Academy in Bradford became one of the most celebrated schools in the country.

Back in 2010, the incoming education secretary, Michael Gove, warned that the poorest children were being left to the worst education while richer families were buying their way to quality education through private schools or expensive houses in catchment areas.

Free schools, he promised, would change this.

“By allowing new schools, we will give all children access to the kind of education only the rich can afford,” Mr Gove said

Nothing represented this ambition better than the Kings Science Academy.

Investigation: DfE failed to secure police investigation into fraud

Quick read: Controversy over free-school land deal

Background: Trio jailed for fraud at Kings Science Academy

One of the first wave of 24 free schools to open, it was to offer an academic education for children in a deprived neighbourhood in Bradford, one of the poorest cities in the North.

Oxbridge graduate and bus driver’s son Sajid Hussain Raza, who had grown up in Bradford, was its founding principal. The school’s motto was “character and knowledge”.

When it opened in September 2011, The Daily Telegraph declared that the school came  “closest to [prime minister] David Cameron’s vision of what a free school should be”.

It also had the backing of Alan Lewis, a prominent businessmen and then vice-chairman of the Conservative Party.

Mr Cameron visited the school in its first year and sent a letter to the head congratulating him on what he had seen.

The Kings Science Academy was to remain high-profile but it is now remembered today for very different reasons.

In 2013 it became embroiled in a fraud scandal following the leak of internal Department for Education investigation report, which said that fabricated invoices had been submitted by the school when it was in the process of being set up.

A high-profile fraud trial followed, resulting in three former members of staff, including the founding principal Hussain Raza, being jailed.

Raza, his sister Shabana Hussain, and the school’s former finance director Daud Khan were jailed after being convicted by a jury at Leeds Crown Court of making payments into their own bank accounts from Department for Education grants given to help set up the Kings Science Academy.

Kings Science Academy: the unanswered questions

Many might consider that the conclusion of this court case marked the end of an unfortunate and embarrassing chapter for free schools and the government of the day.

But vital questions about this scandal remained unanswered. This is not about what happened in Bradford but about what happened in Westminster and Whitehall.

The criminal investigation into the Kings Science Academy started on 31 October 2013, less than a week after the Department for Education published a heavily redacted version of its investigation report into the school.

This report was only published after a leaked draft of the report was sent to Newsnight and it appeared on the DfE website just hours before the BBC programme about the school’s finances went on air on 25 October. At that stage there had been no police investigation.

The Department for Education said at the time that it had informed the police, “who had decided that no further action was necessary.”

The school’s headteacher remained in post, no public sanctions against the school were taken and there had been nothing in the public domain to indicate that the DfE had been aware of alleged fraud at the school for some six months.

But as soon as the matter was made public, a police investigation swiftly followed. West Yorkshire Police charged three people and criminal convictions followed.

So why had nothing happened before the investigation report was leaked?

When this question was asked back in November 2013, it emerged that the matter had wrongly been dealt with as being an information report and had not been passed to the police as a potential crime.

The DfE’s own investigation had uncovered the fraud. And the report dated May 2013 said that this matter should be passed to the police.

The DfE reported the matter with a phonecall to Action Fraud - the Home Office body that handles reports of fraud before passing them on to the relevant police force. At this stage the matter was wrongly classed as being a report of information rather than a crime and therefore it had not been investigated by the police. Action Fraud was said to have apologised for the mistake.

This appeared to exonerate the DfE, which had reported the matter through the correct channels - yet it had somehow slipped through the net through no fault of its own.

However, a freedom of information request shows that, in fact, the DfE had been told some two months earlier that no police investigation was taking place because the matter had been logged as being for information.

The DfE, having phoned in the report of fraud in April 2013, asked for an update on the case on 5 September of that year with a short email to Action Fraud.

In response, Action Fraud told the department that the matter had only been logged as information and it would need to be reported as a crime in order for it to be looked at by the police. The DfE was also told that more information would be needed in order for the police to investigate.

But Tes has revealed today that the DfE did not go back to Action Fraud after this to clarify matters in the following two months

The question is why not? The department knew of, indeed it had found evidence of, fraud at one of its free schools. And after reporting it, the DfE had then been told that these allegations were not being looked at by the police. Why was this not rectified?

When the matters became a public, a police investigation was swiftly launched. But why for six months, when the matter was not in the public domain, did the DfE fail to ensure that police investigated a crime at its flagship free school?

The land deal for flagship free school

Events have moved on. The Kings Science Academy is, in a sense, long gone. The school was rebrokered into the Dixons Academies chain and Dixons Kings, as it is now known, has enjoyed some very successful results. The free-school policy is no longer really at the forefront of education debate and there have been three education secretaries since Mr Gove was in post at Sanctuary Buildings.

However, there are decisions about the way the school was set up - separate to the fraud - that still remain of concern today. Namely the land deal which was agreed for the site on which the school sits.

The leaked draft of the investigation report into the Kings Science Academy revealed that the DfE had agreed to pay £295,960 a year in rent over a 20-year lease for an inner-city site in Bradford to the Hartley Group, a company owned by Mr Lewis.

The value of this deal was questioned when it emerged.

Local councillors suggested that the DfE was paying almost as much in rent for a year as the authority had paid to purchase another secondary school site in the city.

The question that still remains is: is that amount still being paid today? Has the DfE been spending close to £300,000 a year to rent a secondary school site in a deprived area of Bradford, and, if so, what will happen when the lease expires?

The department and Dixons have declined to answer these questions, as Tes is reporting. The DfE said the matter was commercially sensitive.

Opponents of free schools often highlight the controversies over Kings Science Academy to make their case.

However, this story goes beyond the politics of free schools.

These are questions about how public money intended for the education of children has been and is being used by our government.

We deserve answers.